Running axial mass of the nucleon as a phenomenological tool for calculating quasielastic neutrino–nucleus cross sections

We suggest an empirical rule-of-thumb for calculating the cross sections of charged-current quasielastic (CCQE) and CCQE-like interactions of neutrinos and antineutrinos with nuclei. The approach is based on the standard relativistic Fermi-gas model and on the notion of neutrino energy dependent axial-vector mass of the nucleon, governed by a couple of adjustable parameters, one of which is the conventional charged-current axial-vector mass. The inelastic background contributions and final-state interactions are therewith simulated using GENIE 3 neutrino event generator. An extensive comparison of our calculations with earlier and current accelerator CCQE and CCQE-like data for different nuclear targets shows good or at least qualitative overall agreement over a wide energy range. We also discuss some problematical issues common to several competing contemporary models of the CCQE (anti)neutrino–nucleus scattering and to the current neutrino interaction generators.

Primary Extra-axial Glioblastoma: Case Report and Literature Review

Glioblastoma multiforme (GBM) is the most frequent and most aggressive primary brain tumor in adults, mainly located in the cerebral hemispheres. In the literature, few cases of primary GBM have been reported to have radiographic and intraoperative features of extra-axial lesions, leading to a diagnostic dilemma. Despite the advances in imaging modalities, the diagnosis of GBM can be challenging, and it is mainly based on the histopathologic confirmation of the excised tumor. We describe the case of a 76-year-old previously healthy female patient who presented to our hospital due to speech disturbances and cognitive impairment. The diagnosis of the tumor type on magnetic resonance imaging (MRI) was difficult, as the findings were suggestive of a malignant meningioma due to the heterogeneous enhancement of a dural-based mass with a dural tail sign. Moreover, the intraoperative findings revealed an extra-axial mass attached to the dura. A histological examination confirmed the diagnosis of glioblastoma with arachnoid infiltration. The patient underwent adjuvant radiotherapy and concomitant temozolomide treatment, she had clinical improvement postoperatively, and was stable during the six months of follow-up. Glioblastoma should be considered in the differential diagnosis of primary extra-axial mass with atypical and malignant features, especially in elderly patients.

Intracranial meningioma in a pet rat: MRI findings

We herein report the magnetic resonance imaging (MRI) findings in a brain meningioma in a pet rat (Rattus norvegicus domestica). A 1.5-year-old pet rat was referred for depression, ataxia, tremors and bilateral nystagmus; a brain MRI was elected suspecting an intracranial neoplasia. The study was performed with a 0.25 T scanner. The MRI revealed a well-defined oval mass with a heterogeneous appearance, hyperintense in T1 and T2, and with extra-axial localisation and severe brain compression, the mass appeared strongly and diffusely contrast-enhancing. Euthanasia was elected, with the necropsy confirming the presence of a voluminous extra-axial mass. Histologically, a well-differentiated, benign meningotheliomatous meningioma was diagnosed, with the histochemical stains allowing one to exclude a granular cell tumour. To the best of our knowledge, this is the first report of MRI investigations on a pet rat intracranial meningioma.

Primary histiocytic sarcoma in the brain with renal metastasis causing internal ophthalmoparesis and external ophthalmoplegia in a Maine Coon cat

Case summary An 11-year-old neutered male Maine Coon cat was presented for investigation of anisocoria and depression. Neurological examination was consistent with a lesion at the level of the middle cranial fossa, and biochemistry was indicative of moderate renal functional impairment. MRI of the brain identified an extra-axial mass lesion at the level of the middle cranial fossa, T2-weighted hyperintense and strongly homogeneously contrast enhancing with dural tail. The cat was euthanased after 6 weeks of palliative treatment with corticosteroids. Histopathology and immunohistochemistry of the brain, the intra-cranial mass and the renal masses found on necropsy were consistent with histiocytic sarcoma. Relevance and novel information Central nervous system histiocytic sarcoma is a rare finding in cats. This original case report describes the neurological presentation, novel MRI characteristics and pathological findings of suspected primary histiocytic sarcoma affecting the brain with renal metastasis in a cat.

Extra-axial tentorial medulloblastoma: a rare presentation of a common posterior fossa tumour

Medulloblastoma is a common paediatric posterior fossa tumour typically presenting as midline intra-axial mass involving the cerebellar vermis and/or roof of fourth ventricle with typical radiological features. These can be extra-axial in extremely rare instances with less than 50 cases reported so far in literature. We present a case of 18-year-old boy presenting with ataxia and headache. MRI showed dural mass (involving the left tentorium cerebellum) with typical imaging features of extra-axial lesion. The patient underwent near total excision of the tumour. Histopathology along with immunohistochemistry revealed the mass to be medulloblastoma. We present this case to highlight rarity of this location for medulloblastoma and the importance of considering this in the differential diagnosis of atypical posterior fossa extra-axial lesions. This can help in performing other relevant preoperative workup similar on the lines of medulloblastoma and planning of relevant management.

Sino Cranial Aspergillosis Mimicking Skull Base Meningioma- A Case Report and Review of Literature

Fungal infections of the nose and paranasal sinuses can be categorised into invasive and noninvasive forms. Central Nervous System (CNS) Aspergillosis is extremely rare in immunocompetent individuals. Invasive fungal sinusitis affecting CNS commonly poses a diagnostic dilemma on imaging, often confused with neoplastic processes. Here, Authors report a case of invasive sino cranial aspergillosis in immunocompetent individual mimicking a meningioma on imaging. A 46-year-old male patient presented with history of seizure like episode and right eye proptosis to Neurology Department. On Magnetic Resonance Imaging (MRI), there was enhancing T2 weighted hypointense extra-axial mass lesion along right frontal convexity with associated osseous erosion, intraorbital extension and associated sinus disease. Based on clinical presentation and imaging features, initial diagnosis of a aggressive neoplastic lesion was made. Patient subsequently underwent biopsy which showed fungal elements of Aspergillus Fumigatus species. Patient underwent endoscopic sinus surgery and along intravenous and oral antifungal therapy with good response to treatment. This case highlights the key role of imaging including MRI and CT in making accurate diagnosis of fungal sinusitis especially in immunocompetent individuals and differentiate from other entities like meningioma.

Planum Sphenoidale Meningioma: A Rare Location of Skull Base Meningioma

Background: Meningioma is common primary central nervous system tumors. Twenty-five percent of all meningioma consist of skull base meningioma. Planum sphenoidale meningiomas are rare. Planum sphenoidale meningiomas can extend into adjacent areas. Approximately two thirds of patients complain of failing vision in one eye as the first symptom. Case Report: A 32-year-old woman presented with 6-month history of progressively worsening blurred of both of vision. She also complained her smell ability was reduced for 3 months. She had headache for 6 months. The pain was worsening in the morning. She is conscious. A neurologic examination revealed bilateral hyposmia and visual deficits but no weakness. Visus of oculo dextra was 1/300 and visus of oculo sinistra was no light perception. Magnetic resonance imaging (MRI) intravena contrast of brain revealed a large extra-axial mass measured ±6,2x5,9x6 cm centred on planum sphenoidale displacing both frontal lobes. She had an operation of tumor removal with cranio-orbito-zygotomy approach. The tumor, which measured ±7cmx7cmx6 cm, was succesfully removed completely. She gets improvement of smell ability and both visual postoperatively. The histopathology of the tumor revealed meningioma WHO grade I. Discussion: Planum sphenoidale meningiomas present a frequently encountered pathology of the anterior skull base. These meningiomas give rise to an early visual disturbance with relatively slow progression. Displacement of the olfactory tracts and optic chiasm occur when the meningioma extends into the paranasal sinuses and nasal cavity. Clinical presentation and diagnosis often occur in the late stage. Anosmia is one of common finding on physical examination. Postoperative improvement of visual symptoms depends on the preoperative duration of those symptoms.

Extra-axial cerebellopontine angle cavernoma: A case report and review of literature

Background: Extra-axial cavernomas at the cerebellopontine angle (CPA) are rare clinical entity that can radiologically mimic several lesions encountered at this location. Case Description: A 36-year-old female patient referred to our emergency service with acute decreased level of consciousness and vomiting. Neurological examination showed Glasgow Coma Scale of 12 with downbeat nystagmus of the right eye. Brain computed tomography scan and magnetic resonance imaging showed multilobulated extra-axial mass lesion located in the right CPA. The lesion was with various signal intensities in T1- and T2-weighted images suggestive of hemorrhages of different ages. T2 gradient echo sequences showed multiple sinusoid-like channels and diffuse hemosiderin deposition. These figures were compatible with cavernous malformation. The patient was operated by retrosigmoid approach. Dissection of the mass from the trigeminal, facial, vestibulocochlear, and lower cranial nerves was performed and total resection of the tumor was achieved. Histopathological examination confirmed the diagnosis of cavernoma. Conclusion: Although CPA cavernomas are very rare, they should be considered for differential diagnosis when evaluating CPA lesions preoperatively for better intraoperative management and postoperative outcomes.

Giant Solitary Plasmacytoma of Skull: A Case Report

Plasmacytoma is a tumor arising from plasma cell, which mainly grows within soft tissue or within axial skeleton, when it is present as a discreet solitary mass it is called as solitary plasmacytoma & it is rare, we report a 46 years male, presented to us with the complaints of painless swelling in the left frontoparietal region which is about 8.6x6.5cm in diameter, Magnetic resonance imaging revealed an extra axial mass in fronto parietal region with overlying bone destruction mimicking meningioma with bony erosion, we did frontoparietal craniectomy and complete resection of tumor with bony margin subsequently cranioplasty was also done, histopathology of which revealed plasmacytoma,after that we did urinary bence jones protein which was negative. Bang. J Neurosurgery 2020; 10(1): 106-110